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Biomechanical energy harvesting technologies for wearable electronics:Theories and devices

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Friction 2024年第8期12卷 1655-1679页

作者： xiaowen LI Xu ZENG Junwei LI Boyuan LI Yu CHEN xiaosheng ZHANG University of Electronic Science and Technology of China Chengdu 611731China

Wearable biomechanical energy harvesting devices have received a lot of attention recently,benefiting from the rapid advancement of theories and devices in the field of the micro electromechanical system(MEMS).They not only fulfil the requirements for powering wearable electronic devices but also provide an attractive prospect for powering self-powered flexible electronic devices when *** this article,we provide a review of the theories and devices of biomechanical energy harvesting technology for wearable *** different forms of biomechanical energy harvesting mechanisms,including the piezoelectric effect,electromagnetic effect,and electrostatic effect,are investigated in *** fundamental principle of converting other types of energy from the biomechanical environment into electrical energy,as well as the most commonly-used analytical theoretical models,are outlined for each ***,the features,properties,and applications of energy harvesting devices are *** addition,the coupled multi-effect hybrid energy harvesting devices are listed,showing the various possibilities of biomechanical energy harvesting devices for serving as sources,sensors,and ***,we present perspectives on the future trends of biomechanical energy harvesting devices for wearable electronics applications.

关键词： micro electromechanical system(MEMS) nanogenerators biomechanical energy harvesters wearable electronics

Hydrophobic CHA-ZIFs with a junctional trap between cha and d6r cages for adsorption of 2,3-butanediol in aqueous solution

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Chinese Journal of Chemical Engineering 2024年第9期73卷 90-100页

作者： Lifang Ge Meizhen Gao xiaosheng Zhang Jiang Wang Qi Shi Jinxiang Dong College of Chemical Engineering and Technology Shanxi Key Laboratory of Chemical Product EngineeringTaiyuan University of TechnologyTaiyuan 030024China

The adsorption and separation of diols from dilute aqueous solution using hydrophobic materials is very challenging due to the strong diol-water hydrogen-bonding interactions. Herein, we screened hydrophobic zeolitic imidazolate frameworks(ZIFs) with chabazite(CHA) topology for separation of 2,3-butanediol(2,3-BDO) and 1,3-propanediol(1,3-PDO), which had junctional and hydrophobic traps matching the two end methyl groups of the 2,3-BDO molecule. Based on CHA-ZIFs with the same small-sized ligand 2-methylimidazole(mIm) and different large-sized ligand benzimidazole derivatives(RbIm),CHA-ZIFs with larger surface areas were obtained by the addition of excess small-sized ligand mIm in the synthesis process. We showed that all of the hydrophobic CHA-ZIFs preferentially adsorbed 2,3-BDO over 1,3-PDO by static batch adsorption and dynamic column adsorption experiments. But ZIF-301 and ZIF-300 with halogen groups exhibited better adsorptive separation performance for 2,3-BDO/1,3-PDO than ZIF-302 with methyl groups. For a typical ZIF-301, its adsorption capacity for 2,3-BDO was 116.4 mg·g^(-1)and selectivity for 2,3-BDO/1,3-PDO was 3.8 in dynamic column adsorption of the binary-component system(2,3-BDO/1,3-PDO: 50 g·L^(-1)/50 g·L^(-1)). Computational simulations revealed that 2,3-BDO preferentially adsorbed in a trap at the junction between the cha and d6r cages of CHA-ZIFs,meaning the strong host-guest interactions. Therefore, the hydrophobic CHA-ZIFs with a junctional trap were promising candidate materials for adsorbing 2,3-BDO, which also provided a new perspective for separating diols in dilute aqueous solutions.

关键词： Adsorption Separation Aqueous solution Zeolitic imidazolate frameworks Junctional and hydrophobic trap Diols

Multi-Period Resilient Model for VSC-Based AC-DC HDS Considering Public-Safety Power Shutoff to Mitigate Wildfires

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 821-833页

作者： Zekai Wang Tao Ding xiaosheng Zhang Chenggang Mu Pengwei Du Fangxing Li School of Electrical Engineering Xi'an Jiaotong UniversityXi'an 710049China Electric Reliability Council of Texas AustinTX76574 USA Department of Electrical Engineering and Computer Science The University of TennesseeKnoxville(UTK)TN37996USA

This paper proposes a voltage source converter (VSC) -based AC-DC hybrid distribution system (HDS) resilient model to mitigate power outages caused by wildfires. Before a wildfire happens, the public-safety power shutoff (PSPS) strategy is applied to actively cut some vulnerable lines which may easily cause wildfires, and reinforce some lines that are connected to critical loads. To mitigate load shedding caused by active line disconnection in the PSPS strategy, network reconfiguration is applied before the wildfire occurrence. During the restoration period, repair crews (RCs) repair faulted lines, and network reconfiguration is also taken into consideration in the recovery strategy to pick up critical loads. Since there exists possible errors in the wildfire prediction, several different scenarios of wildfire occurrence have been taken into consideration, leading to the proposition of a stochastic multi-period resilient model for the VSC-based AC-DC HDS. To accelerate the computational performance, a progressive hedging algorithm has been applied to solve the stochastic model which can be written as a mixed-integer linear program. The proposed model is verified on a 106-bus AC-DC HDS under wildfire conditions, and the result shows the proposed model not only can improve the system resilience but also accelerate computational speed.

关键词： AC-DC hybrid distribution system restoration network reconfiguration progressive hedging public safety power shutoffs strategy resilience

Investigation and characterization of an arc-shaped piezoelectric generator

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Science China(Technological Sciences) 2013年第11期56卷 2636-2641页

作者： HAN MengDi LIU Wen ZHANG xiaosheng MENG Bo ZHANG HaiXia Institute of Microelectronics Peking University Peking University Shenzhen Graduate School

A novel arc-shaped piezoelectric generator based on flexible PVDF thin film is presented and systemically *** a periodical external force,the generator can produce peak voltage of 45.6 V and peak power of 30.7μ*** maximum power density reaches 38.4μW/cm3with a 4 cm×2 cm×100μm device,at the optimum load resistance of 33.33 *** influence of frequency,size dimension and load resistance are investigated through experimental *** this high output arc-shaped generator,capacitors can be effectively charged and three commercial LEDs have been directly lighted without any energy storage unit.

关键词： piezoelectric generator arc-shaped PVDF high output self-powered system

Optimization of the Purification Methods for Recovery of Recombinant Growth Hormone from Paralichthys olivaceus

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Journal of Ocean University of China 2013年第1期12卷 169-174页

作者： ZANG xiaonan ZHANG Xuecheng MU xiaosheng LIU Bin College of Marine Life Sciences Ocean University of China Yellow Sea Fisheries Research Institute Chinese Academy of Fishery Sciences

This study aimed to optimize the purification of recombinant growth hormone from Paralichthys olivaceus. Recombinant flounder growth hormone （r-fGH） was expressed by Escherichia coli in form of inclusion body or as soluble protein under different inducing conditions. The inclusion body was renatured using two recovery methods, i.e., dilution and dialysis. Thereafter, the refolded protein was purified by Glutathione Sepharase 4B affinity chromatography and r-fGH was obtained by cleavage of thrombin. For soluble products, r-fGH was directly purified from the lysates by Glutathione Sepharase 4B affinity chromatography. ELISA-receptor assay demonstrated that despite its low receptor binding activity, the r-fGH purified from refolded inclusion body had a higher yield （2.605 mg L^-1） than that from soluble protein （1.964 mg L^-l）. Of the tested recovery methods, addition of renaturing buffer （pH 8.5） into denatured inclusion body yielded the best recovery rate （17.9%）. This work provided an optimized purification method for high recovery of r-fGH, thus contributing to the application of r-fGH to aquaculture.

关键词： Paralichthys olivaceus growth hormone fusion expression purification receptor binding activity

SGT-Net: A Transformer-Based Stratified Graph Convolutional Network for 3D Point Cloud Semantic Segmentation

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Computers, Materials & Continua 2024年第6期79卷 4471-4489页

作者： Suyi Liu Jianning Chi Chengdong Wu Fang Xu xiaosheng Yu Faculty of Robot Science and Engineering Northeastern UniversityShenyang110167China State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang110016China Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang110169China SIASUN Robot&Automation Co. Ltd.Shenyang110169China

In recent years,semantic segmentation on 3D point cloud data has attracted much *** 2D images where pixels distribute regularly in the image domain,3D point clouds in non-Euclidean space are irregular and inherently ***,it is very difficult to extract long-range contexts and effectively aggregate local features for semantic segmentation in 3D point cloud *** current methods either focus on local feature aggregation or long-range context dependency,but fail to directly establish a global-local feature extractor to complete the point cloud semantic segmentation *** this paper,we propose a Transformer-based stratified graph convolutional network(SGT-Net),which enlarges the effective receptive field and builds direct long-range ***,we first propose a novel dense-sparse sampling strategy that provides dense local vertices and sparse long-distance vertices for subsequent graph convolutional network(GCN).Secondly,we propose a multi-key self-attention mechanism based on the Transformer to further weight augmentation for crucial neighboring relationships and enlarge the effective receptive *** addition,to further improve the efficiency of the network,we propose a similarity measurement module to determine whether the neighborhood near the center point is *** demonstrate the validity and superiority of our method on the S3DIS and ShapeNet *** ablation experiments and segmentation visualization,we verify that the SGT model can improve the performance of the point cloud semantic segmentation.

关键词： 3D point cloud semantic segmentation long-range contexts global-local feature graph convolutional network dense-sparse sampling strategy

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工业数字化转型安全风险分析

现代工业经济和信息化 2025年第1期15卷 71-73,81页

作者：郑小升刘瑷琳荆敏北京邮电大学世纪学院基础教学部北京102101 吉林外国语大学马克思主义学院吉林长春130117

分析了工业企业数字化转型聚焦实现智能制造,其本质是通过大数据、人工智能、3D打印、数字孪生等技术将传统制造业重构为一个智慧的“物理-信息”系统,进而揭示出这一重构面临诸多与传统信息化建设不同的新的安全挑战,集中体现为需要在... 详细信息

分析了工业企业数字化转型聚焦实现智能制造,其本质是通过大数据、人工智能、3D打印、数字孪生等技术将传统制造业重构为一个智慧的“物理-信息”系统,进而揭示出这一重构面临诸多与传统信息化建设不同的新的安全挑战,集中体现为需要在应对“逆安全”、新旧安全叠加、防范系统性风险、依靠和保护数据、业务领域重构等多种复杂因素中统筹实现新安全。

关键词：工业企业数字化转型安全风险新安全

Remaining useful life prediction based on nonlinear random coefficient regression model with fusing failure time data

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Journal of Systems Engineering and Electronics 2023年第1期34卷 247-258页

作者： WANG Fengfei TANG Shengjin SUN xiaoyan LI Liang YU Chuanqiang SI xiaosheng Department of Mechanical Engineering Rocket Force University of EngineeringXi’an 710025China

Remaining useful life(RUL) prediction is one of the most crucial elements in prognostics and health management(PHM). Aiming at the imperfect prior information, this paper proposes an RUL prediction method based on a nonlinear random coefficient regression(RCR) model with fusing failure time ***, some interesting natures of parameters estimation based on the nonlinear RCR model are given. Based on these natures,the failure time data can be fused as the prior information reasonably. Specifically, the fixed parameters are calculated by the field degradation data of the evaluated equipment and the prior information of random coefficient is estimated with fusing the failure time data of congeneric equipment. Then, the prior information of the random coefficient is updated online under the Bayesian framework, the probability density function(PDF) of the RUL with considering the limitation of the failure threshold is performed. Finally, two case studies are used for experimental verification. Compared with the traditional Bayesian method, the proposed method can effectively reduce the influence of imperfect prior information and improve the accuracy of RUL prediction.

关键词： remaining useful life(RUL)prediction imperfect prior information failure time data nonlinear random coefficient regression(RCR)model

Remaining useful life prediction of aero-engines based on random-coefficient regression model considering random failure threshold

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Journal of Systems Engineering and Electronics 2023年第2期34卷 530-542页

作者： WANG Fengfei TANG Shengjin LI Liang SUN xiaoyan YU Chuanqiang SI xiaosheng College of Missile Engineering Rocket Force University of EngineeringXi’an 710025China

Remaining useful life(RUL)prediction is one of the most crucial components in prognostics and health management(PHM)of *** paper proposes an RUL prediction method of aero-engines considering the randomness of failure ***,a random-coefficient regression(RCR)model is used to model the degradation process of ***,the RUL distribution based on fixed failure threshold is *** prior parameters of the degradation model are calculated by a two-step maximum likelihood estimation(MLE)method and the random coefficient is updated in real time under the Bayesian *** failure threshold in this paper is defined by the actual degradation process of *** that,a expectation maximization(EM)algorithm is proposed to estimate the underlying failure threshold of *** addition,the conditional probability is used to satisfy the limitation of failure ***,based on above results,an analytical expression of RUL distribution of aero-engines based on the RCR model considering random failure threshold(RFT)is derived in a ***,a case study of turbofan engine is used to demonstrate the effectiveness and superiority of the RUL prediction method and the parameters estimation method of failure threshold proposed.

关键词： aero-engine remaining useful life(RUL) random failure threshold(RFT) random-coefficient regression(RCR) parameters estimation